The disclosure relates to a method for operating a braking device, in particular a parking-brake device, of a vehicle, said device comprising at least one wheel braking device having an electrically motorized actuator, wherein the actuator comprises an electric motor and an actuator element that can be moved by means of the electric motor, wherein the actuator element can be moved into a brake application position so as to actuate the wheel braking device and can be moved into a brake release position so as to release the wheel braking device, and wherein a movement travel of the actuator element is monitored at least when releasing the wheel braking device.
In addition, the disclosure relates to a device for operating a braking device of this type, and also a braking device.
Methods and devices and also braking devices of the type mentioned in the introduction are known from the prior art. A wheel of a vehicle is blocked or released by means of an electrically motorized actuator in the case of a parking brake by means of a wheel braking device. For this purpose, an actuator element is displaced into a brake application position in which typically brake linings of the wheel braking device are pressed against a brake disk that is connected to a wheel of the vehicle in a non-rotatable manner, or said actuator element is displaced into a brake release position in which the actuator element is moved backwards to such an extent that the brake disk can move freely between the brake linings. Modern actuators for parking-brake devices of this type are used without rotational speed sensors for reasons of cost and the installation space required. For this reason, an estimation of travel can be performed merely by way of the supply voltage and the motor current so as to correctly position the actuator element. The estimation of travel is required so as to set the correct free play, in other words the spacing between the brake linings and the brake disk, when releasing the braking device. The correct free play is particularly important for a safe driving operation; a free play that is not properly set can lead by way of example to premature wear and tear and is therefore to be avoided.